Water heater unit

ABSTRACT

A water heating and supply system is provided, comprising in combination, a water storage tank having a cold water supply inlet and a heated water service outlet and supply conduit system, and a heater shroud extending into the upper level of the tank; the shroud being arranged at its inner end in closed fluid flow communication with an intake manifold means drawing water from substantially throughout the vertical range of the interior of the tank. A heater is disposed within the shroud and operates under control of a heat supply regulator. A by-pass circulating conduit system is provided including a continuously operating pump having its intake in fluid communication with the interior of said shroud adjacent the outer end thereof and its discharge arranged to deliver water into the bottom level of said tank. The return from the heated water supply system is arranged in open communication with said by-pass conduit system, Hence, whenever water is withdrawn from the service outlet, replacement cold feed water moves through said supply inlet and is thereby mixed into the water being circulated throughout the entire vertical extent of the tank from which the intake manifold draws water from substantially all levels within the tank. A water temperature sensor is disposed in the region of service water withdrawal from the heater shroud, and is operable to regulate the heat supply. The invention features improved water temperature stratification control in systems designed for such purposes.

Elite Clark, Jr. et a1.

[ WATER HEATER T The Patterson-Kelley Co., Stroudsburg, Pa.

22 Filed: May28, 1970 211 Appl.No.: 41,401

[73] Assignee: lnc., East [52] US. Cl.. ..l65/39, 165/108 [51] Int.Cl..- ..1B60h l/00 [58] Field ofSearch ..l65/39,40,l08,35, 132;

[56] References Cited UNITED STATES PATENTS 3,276,517 10/1966 Lowe..165/39 Primary ExaminerCharles Sukalo AttorneyBean & Bean [5 7]ABSTRACT A water heating and supply system is provided, comprising incombination, a water storage tank having a cold water supply inlet and aheated water service outlet and supply conduit system, and a heatershroud extending into the upper level of the tank; the shroud beingarranged at its inner end in closed -fluid flow communication with anintake manifold means drawing water from substantially throughout thevertical range of the interior of the tank. A heater is disposed withinthe shroud and operates under control of a heat supply regulator. Aby-pass circulating conduit system is provided including a continuouslyoperating pump having its intake in fluid communication with theinterior of said shroud adjacent the outer end thereof and its dischargearranged to deliver water into the bottom level of said tank. The returnfrom the heated water supply system is arranged in open communicationwith said by-pass conduit system, Hence, whenever water is withdrawnfrom the service outlet, replacement cold feed water moves through saidsupply inlet and is thereby mixed into the water being circulatedthroughout the entire vertical extent of the tank from which the intakemanifold draws water from substantially all levels within the tank. Awater temperature sensor is disposed in the region of service waterwithdrawal from the heater shroud, and is operable to regulate the heatsupply. The invention features improved water temperature Stratificationcontrol in systems designed for such purposes.

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GBM-MM A TTOR/VEYS WATER HEATER UNIT GENERAL DESCRIPTION Generallystated, the invention contemplates an improved method of heating waterand storing it in a reduced size accumulator tank so as to have itavailable to supply either constant or intermittent demands for eithersmall or large quantities of hot water. The invention may be practicedin combination with a storage water tank of any preferred shape; andalthough any suitable type of heat supply medium may be employed, asshown herein a bundle of return-bent steam conveying tubes enclosedwithin a shroud which extends into the tank is employed as the heaterunit. The tube bundle may comprise any desired number of banks ofretum-bent tubes arranged in spaced relation; and the tubes may bearranged to conduct steam or other hot fluid from any suitable source,and to deliver any condensates through a suitable trap.

The system features an arrangement which may be readily constructed inunit form; fully self-contained, and requiring minimum floor space; andis therefore suitable for installation in out-of-way locations. It isreadily connected to existing piping systems, and normally draws uponthe associated steam generating boiler or the like in such limitedmanner as to avoid interference with constant steam pressures at otherassociated steam operated equipment. Thus, the heater of the presentsystem will normally operate to even-out the boiler load, therebyimproving its efficiency and life span.

THE DRAWING The drawing figure presented herewith is a longitudinalsectional view through a water storage tank embodying a typical watercirculation and heater control system of the present invention.

DETAILED DESCRIPTION As shown in the drawing herewith, the invention maybe embodied ina system including a water storage tank having a coldwater inlet connection as indicated at 12 leading into the bottom levelthereof. A tube bundle for heating the water, as indicated at 14 ishoused within a shroud 16 which extends into the interior of the tank10. The shroud 16 is closed at its inner end by means of an intakemanifold such as may be provided by a vertically standing pipe orconduit 18 which is either open or closed at its ends and in any case isprovided with water intake means drawing water from substantially alllevels of the interior of the tank; such as by being formed atvertically spaced intervals with saw cuts or other apertures asindicated at 19. A series of staggered baffles are optionally carried bythe tubes or otherwise supported in the shroud as shown at 20, to forcethe circulating water to traverse a zig-zag path through the tubebundle, as will be explained more fully hereinafter.

At its outer end the shroud 16 is flanged and carries a tube sheet 21through which the open ends of the tubes 14 extend into opencommunication at their opposite ends with the interior chambers of ahorizontally partitioned bonnet 22 which is similarly flanged and boltedinto cooperation with the tube sheet and thus to the end of the shroud16. Steam or any other suitable heating fluid is introduced as by meansof a conduit 24 into the upper portion of the bonnet, from whence itflows through the return bent tubes 14 and then into the lower portionof the bonnet for discharge through a condensate trap or the like asindicated at 26. Passage of steam through the conduit 24 and into thesystem is controlled as by means of a flow regulator as is indicated at28. The regulator 28 is in turn controlled by a temperature sensing"bulb or the like, such as is shown at 30 located in the hot waterwithdrawal area provided by a hot water service outlet conduit 32, andis connected to the flow regulator 28 by a control line 34.

The hot water take-off connection 32 draws from the outer end of theshroud 16 and delivers hot water which is freshly heated by the tubebundle to the heated water supply system,

regardless of from which portion of the storage tank it may have beendrawn. Also, leading away from the outer end of the shroud 16 is a waterby-pass circulating conduit 36 which leads to a constantly running pump38 delivering through a conduit 39 into a connection 40 discharging intothe bottom of the tank 10. Hence, operation of the pump 38 draws waterthrough the heating tube bundle and delivers it (as indicated by theflow directional arrows) into the bottom level of the tank whereupon itproceeds to intimately mix into and with the water occupying the upperlevels of the tank.

Thus, it will be appreciated that operation of the pump 38 will providea constant circulation of water drawn through the manifold apertures 19from substantially all levels of the tank 10; through the heater shroud,around the sensing bulb 30; through the conduit 36; the conduit 39; andthen back into the lower portion of the tank 10. Hence, the water in thestorage system will be constantly circulating in accordance with thedirectional arrows shown in the drawing herewith. Also, it will beappreciated that whenever heated water is withdrawn through the serviceconduit 32 corresponding amounts of cold feed water will enter the tankthrough the inlet 12 and will be directed by the deflector 41 so as toblend directly into the pump circulated stream of water entering thetank through connection 40. As shown at 42, the return from the heatedwater supply conduit system is connected into the pump-circulatingconduit system so as to strategically contribute its input to thetemperature blending operation.

Thus, it will be understood that because the intake manifold 18 drawswater into and through the heater component of the system from allvertical levels of the tank interior, the invention provides an improvedStratification system as well as an improved feed water supply system;operating automatically to blend heated water into the cold feed waterentering the tank and thereby reducing the water temperaturedifferential within the tank 10 and utilizing formation of temperatureStratification patterns within the tank.

It is to be understood that whereas the drawing illustrates employmentof a vertically apertured pipe 18 disposed inside the body of the tank10 for all-level intake of water to the heater shroud, the invention isnot limited to use of that specific form of manifold arrangement andcontemplates use of any equivalent thereto in combination with the waterinput, by-pass circulation, and return arrangements as set forth hereinwhereby an overall improved storage water heating system is provided.

We claim:

1. A water heating and storage system of the immersion heater typecomprising,

a water carrying storage tank,

an immersion heater extending into an upper level portion of said tankand comprising an elongate shroud projecting through a wall portion ofsaid tank and having a heat supply means disposed within said shroud forheating water moving therethrough,

a hot water service withdrawal connection into and leading from theouter end of said shroud,

a heat supply regulator responsive to the water temperature in theregion of said withdrawal connection,

a storage water circulation by-pass system including a pump drawingwater from interiorly of said shroud and discharging into the main bodyportion of said tank,

and replacement water supply means delivering into said tank,

said shroud having its intake end portion in sealed fluid communicationwith vertically disposed tank water intake manifold means having fluidflow open communication with the water interiorly of said tank atsubstantially all vertical levels thereof.

2. A water heating system as set forth in claim 1, wherein said shroudextends both inwardly and outwardly of said tank wall and wherein saidservice water withdrawal and circulating by-pass and heat supplyregulator devices are connected into the outer end of said shroud.

S. A water heating system as set forth in claim 4 wherein saidreplacement water supply means includes a cold water inlet and a heatedwater return inlet both leading into the bottom level of said tank.

6. A water heating system as set forth in claim 5 wherein said coldwater inlet is provided with means causing inflowing water to bedeflected away from said manifold means and substantially across thelower level of said tank.

1. A water heating and storage system of the immersion heater typecomprising, a water carrying storage tank, an immersion heater extendinginto an upper level portion of said tank and comprising an elongateshroud projecting through a wall portion of said tank and having a heatsupply means disposed within said shroud for heating water movingtherethrough, a hot water service withdrawal connection into and leadingfrom the outer end of said shroud, a heat supply regulator responsive tothe water temperature in the region of said withdrawal connection, astorage water circulation by-pass system including a pump drawing waterfrom interiorly of said shroud and discharging into the main bodyportion of said tank, and replacement water supply means delivering intosaid tank, said shroud having its intake end portion in sealed fluidcommunication with vertically disposed tank water intake manifold meanshaving fluid flow open communication with the water interiorly of saidtank at substantially all vertical levels thereof.
 2. A water heatingsystem as set forth in claim 1, wherein said shroud extends bothinwardly and outwardly of said tank wall and wherein said service waterwithdrawal and circulating by-pass and heat supply regulator devices areconnected into the outer end of said shroud.
 3. A water heating systemas set forth in claim 1, wherein said heat supply means comprises asteam conducting bundle of return bent tubes.
 4. A water heating systemas set forth in claim 2 wherein said manifold means comprises a conduitextending vertically inside said tank substantially throughout thevertical extent thereof and having intake apertures so arranged as todraw water from substantially all levels within said tank for deliveryinto said shroud.
 5. A water heating system as set forth in claim 4wherein said replacement water supply means includes a cold water inletand a heated water return inlet both leading into the bottom level ofsaid tank.
 6. A water heating system as set forth in claim 5 whereinsaid cold water inlet is provided with means causing inflowing water tobe deflected away from said manifold means and substantially across thelower level of said tank.